Process for converting oils and simultaneously recovering asphalt



Oct. 18, 1932. E W BEARDSLEY ET AL 1,883,745

PROCESS FOR CONVERTING OILS AND SIMULTANEOUSLY RECOVERING ASPHALT Original Filed Jan. 23, 1929 INVENTOR EoW//v WEARsLEy c? ALBERT P 5A VCHS Patented Oct. I, 1932 STATES PATENT OFFICE EDWIN IFJ. BEARDSLEY, OF LOS ANGELES, CALIFORNIA, .AND ALBERT 13.l SACHS,l OF BROOKLYN, NEW YORK, ASSIGNOBS TO PETROLEUJYI CONVERSION CORPORATION, OF NEVI YORK, N. Y., A CORPORATION OF DELAWARE A PROCESS FOR CONVEETING OILS AND SIMULTANEOUSLY RECOVERING ASPHALT Application filed January 23, 1929, Serial No, 334,396. Renewed January 14, 1932.

The present invention relates to the recovering of asphalt-from oils containing same with the simultaneous conversion lof either the non-asphaltic portions of such oil, or of other oils. In the process of refining asphalt-base crude petroleums or the topped or residual oils produced from them, it is usual to produce an'oil termed a flux oil, which is the residue, after asv much as possible of the gasoline, kerosene, gas-oil, etc., has been removed from the crude. This flux oil is then heated carefully and slowly, using a low` fire, and generally with the use of steam to prevent pyrolytic decomposition of the residue, and this heating is continued until enough of the liquid and semi-liquid constituents of the flux oil have been distilled out to give the residue the desired viscosity or so-called penetration to constitute an unblown asphalt. In other cases the flux oil obtained is steamed and blownwith air to produce a. blown asphalt. The steaming and blowing are continued until a product of the desired penetration is obtained. y `When it is attempted to employ such a process, for example, in connection-with the cracking or conversion of the oil by the usual methods, it is found that due to the cracking conditions to which the asphaltic constituents are subjected, the` asphaltic residue 0btainedis of much less value. We have now discovered that the process of conversion and that of distilling asphalt-base oils may be successfully combined in the vcase in which V the cracking isbrought about by the use of a heat carrier gas. In other words, we have found that the products from the reaction chamber of such a process, which include the carrier gas which has been physically mingled with the oil or oil vapor, provide an excellent medium for treatment of the asphalt bearing oil whereby the non-asphaltic constituents thereof may be removed, while at the same time the products from said reaction chamber are reduced in temperature to a suitable degree, and are deprived of substantially all of the free carbon which they may contain. Due to the presence of the large quantities of gas, the evaporation of the non-asphaltic con- 50 stituents Vis facilitated whereby a lresidue `is obtained which is equal to, or superior to, such residues obtained by vacuum distillation. yIn the operation of a preferred embodiment of our invention, means are provided for returning to the conversion chamber portions of the non-asphaltic constituents which are heavier than those desired as the preferred product of the conversion system, as, for example, motor fuels.

Our invention will be best understood from the following detailed description thereof, taken with the annexed drawing, in which we have illustrated a plant embodying our invention in its preferred form.

Referring to said drawing, and first describing briefly the conversion process to which my invention is particularly applicable, 10 denotes the reaction chamber into which oil vapor is fed from evaporator l1 through a pipe 12. For the purpose of accomplishing the conversion of such vapor, a supply of heated carrier gas, conveniently of hydrocarbon origin, is introduced into said chamber through a pipe 13, the heating of said gas lbeing accomplished by means of a regenerative heating element or hot blast stove 14; into which the gas hasbeen introduced through a` vpipe 15. Due to the heat contained in thecarrier gas, the desired conversion is brought about in said chamber 10 and the non-liquid products therefrom are removed through a pipe 16 and introduced into `a gas and liquid contact chamber or column 17. Y

The asphalt bearing oil which is to be subj ected to distillation is fed into said chamber 17 and is introduced in the system conveniently through the pipe 20, leading to storage chamber 21, pipey 22, and pump 23 Iin the circuit of said pipe. Pipe 22 terminates in a spray nozzle 23a, preferably in the top of said chamber 17, which latter preferably contains filler material 24 providing an extended surface contact between the gas and liquid constituents. The temperature of the products from the reaction chamber, which may be in the neighborhood of 900 F., is suflicient to vaporize the non-asphaltic constituents of the asphalt bearing oil, owing to the partial pressures exerted on said constituents by said products. The exact temperature obtaining in said chamber 17 may be controlled with considerable accuracy by the amount of asphalt bearing oil which is admitted and by the circulation thereof through heat exchangers by means of pump 23. Furthermore, due to the scrubbing action of the admitted oil, substantially all of the entrained carbon in said reaction products is removed.

Due to the fact t iat the lower limit of the temperature in said scrubbing chamber is suliiciently high, e. g., around 400 F., little or none of the vapor products from said reaction chamber will be condensed out and added to the asphaltic residues obtained, it"

being noted that because of the presence of the large quantity of the relatively non-condensible heat-carrier gas, the partial pressures of the hydrocarbon vapors will be very low so that the hydrocarbon constituents which it is desired to have in the vapor state will leave the scrubber as vapor even though their boiling points under atmospheric pressure are considerably higher than 400O F.

The non-liquid products from said chamber 17 are conveyed therefrom by a pipe 25 through which they are conveyed to preferably a column 26 in the nature of a rectifier wherein such products are subjected to the action of a liquid oil at lower temperatures whereby products heavier than the desired productare condensed out. As shown, this liquid oil may be the oil which it is desired to admit more or less directly into the reaction chamber after same has been vaporized in the evaporator 11. This oil is admitted to the system through pipe 27 and pump 27a and will give up its low boiling constituents in rectilier 26, should it contain any, due to the conditions obtaining therein. rEhe liquid products from said rectifier are withdrawn through a pipe 28, passed preferably through a heat exchanger 29 and admitted to vaporizer 11 by means of a pipe 30. Pipe 30 also has in its circuit a pump 31 for feeding said oil to the vaporizer 11.

rlhe non-liquid products from column 26 are led therefrom through a pipe 32 into a condenser 33, and thence to an accumulator 34 wherein the desired liquid product of the system is recovered. The gas remaining uncondensed, including the original carrier gas, is led from accumulator 34 through a pipe 35, blower 36, absorber 37, wherein the lighter vapors are further recovered, pipe 38, a heat exchanger 39 in which it is heated, and pipe 15 leading to the heating element 14 already mentioned. ln circuit with pipe 33 is also a gas holder 40 for holding excess gas, the same communicating with pipe 33 by means of a pump 44 and pipe 42.

The asphalt containing residue produced by contact of the oil admitted to the chamber 17 is removed therefrom through pipe 43. Desirably this oil, which contains considerable heat units, abstracted from the products from the reaction chamber is passed in heat exchange relationship with ther products of the system whereby such excess is recovered. Y Accordingly, pipe 43, through which the hot oil from said chamber is passed, communicates with heat exchanger 29 already mentioned wherein the heat from said oil is added to the oil on its way to the evaporator 11. From heat exchanger 29 the asphalt-ic residue passes through a pipe 44a to a second heat exchanger 39 already mentioned, where the heat in such oil is imparted to the carrier gas on its way to the heating element 14. From heat exchanger 39 the oil is passed through a pipe 45 back to storage chamber 21. F rom said chamber the oil, which, desirably, may have been recycled a number of times, is led therefrom through a pipe 46 into a storage chamber 47. ln such chamber the suspended carbon in such oil settles out and the supernatent liquid withdrawn through a pipe 43. Y

lt will be evident from the foregoing that where the asphaltic base oil contains constituents of higher boiling point than motor fuels, for example, and of lower boiling point than the asphaltic constituents themselves, such middle boiling portions will be subjected to rectification in the Column 26' and the non-vaporized portions returned to the vapo izer 11, where they are subjected to vaporizing conditions and the produced vapor products added to those fed to the reaction chamber through pipe 12.

The asphaltic residue obtained in the storage chamber 21 is ordinarily recirculated through the system unt-il it has acquired the desired penetration and depending upon the asphaltic base crude originally supplied to the system yields an asphalt of high utility and commercial value. Such asphaltie residue is suitable for many purposes without blowing, although if it is desired to blow this material, it may be led directly to a still (not shown) and blown before it has a chance to lose a substantial portion of its sensible heat.

t will be obvious that the oil which undergoes conversion is admitted to the system both through pipe 27 to the rectifier 26 and also through the pipe 2O leading to the storage chamber 21, and that the proportion of asphalt-bearing oil admitted through the pipe 2O to the total oil admitted to the system may be as large as desired, provided that the proper conditions are maintained in the rectiiier 26.

We wish it understood that various features not relating specifically to the recovery of asphaltic residues are not claimed herein because they form no part of the present invention, certain of said features being claimed in the application of Edwin Vil. Beardsley, Serial No. 266,535, filed April 2, 1928.

We claim:

l. In the process of converting hydrocarbon oils into products suitable as motor fuels, and simultaneously obtaining asphalt from oils containing same, in admiXture with compounds of lighter molecular weight than asphalt the steps which consist in first subjecting said hydrocarbon oils first mentioned to conversion conditions by contacting same with a heated heat carrier gas physically `mingled therewith in a closed chamber, leading the gas and vapor products produced in said chamber therefrom, adding to said stream of products in a second chamber, said asphalt-bearing oil also containing fractions lighter than asphalt, so controlling the teinperature in said second chamber as to vaporize the fractions lighter than asphalt without dropping out of said streamof productsv pounds of lighter molecular weight than asphalt the steps which consist in first subjecting said hydrocarbon oils first mentioned to conversion conditions by contacting same with a heated heat carrier gas physically mingled therewith in a closed chamber, leading the gas and vapor products lproduced in said chamber therefrom, adding to said stream of products in a second chamber, said asphalt bearing oil also containing fractions i lighter than as halt iassinfr the oras and va- :n a l n b por products from said second chamber and subjecting them to conditions producing liquefaction of said products suitable as motor fuels, withdrawing the asphalt bear- -5 ing oil from said second chamber, cooling said oil and repassing same back intosaid second chamber and controlling the evaporation of the non-asphaltic constituents of said oil by varying the degree of cooling thereof.

4. ln the process of converting asphaltbearing oils into compounds suitable as motor fuels and simultaneously obtaining asphalt therefrom, the steps which consist in 'Y first subjecting hydrocarbon oil, freed substantially from containedasphalt, to conversion conditions by contacting same with a heated heat-carrier gas physically mingled therewith in a closed chamber, leading the stream of admiXed gas and vapor products from said chamber, adding to said stream of products in a second chamber said asphaltcontaining oil, so controlling the temperature in said second chamber as to vaporize fractions lighter than asphaltwhile retaining in said stream, products which it is desirable to subject to conversion conditions, passing the gas and vvapor products from said second chamber and subjecting them to conditions producing liquefaction of said compounds which'it is desiredv to convert but retaining in the gas and vapor stream the vapor of said products suitable as motor fuels, then subjecting said products to condensing conditions producing liquefaction of said products suitable'as moto-r fuels, and returning said separated products which it is desired to convert back into said chamber first mentioned.

5. In the process of converting hydrocarbon oils into motor fuels and simultaneously obtaining asphalt from asphalt-beary ing oils, the steps which consist in subjecting said hydrocarbon oil first mentioned, freed substantially of asphalt, to conversion conditions by contacting same with a heated heat-carrier gas vphysically mingled therewith in a closed chamber wherein conversion takes place and carbon is formed, leading the gas and vapor products produced in said` lighter than asphalt while retaining in said l stream of products the vapor of fractions which it is desirable to subject to conversion conditions, passing gas and Vapor products from said second chamber and subjecting them to conditions producing liquefaction of said products which it is desired to convert and then separately producing liquefaction of said compounds suitable as motor fuels, and utilizing the unvaporized portion of said asphalt-bearing oil to heat products destined for the reaction chamber but without adding thereto the removed carbon. i

6. ln the process of converting hydrocarbon oils into products suitable as motor fuels and simultaneously obtaining asphalt from oils containing same i'n admiXture with compounds of lighter molecular weight than asphalt, the steps which consist in subjecting asphalt-free oil to conversion with the aid of a heat-carrier gas in a conversion Zone as a result of which free carbon is formed and is entrained in the vapor products of the conversion reaction, passing the conversion products into a scrubbing zone and cyclicly circulating a scrubbing liquid comprising an asphalt-bearing oil through said scrubbing zone and through a heat exchange zone thereby causing said scrubbing liquid t0 entrain and remove heat from said conversion prodf ucts in said scrubbing zone and also to Vaporize from said scrubbing liquid constitu ents lighter than said contained asphalt which is thereby separated out, and further to transfer Such heat to a product destined for said reaction Zone which is passed through the heat exchange zone in indirect thermal Contact with the scrubbing liquid. ln testimony whereof We have aii'ixed our signatures to this specification. u; EDY/VIN W. BEARDSLEY.

ALBERT P. SACHS. 

